Inspection arrangement for an automatic sewing apparatus



Oct. 4, 1966 P. SCHWENDINGER 3,276,577

INSPECTION ARRANGEMENT FOR AN AUTOMATIC SEWING APPARATUS Filed Nov. 10,1964 5 Sheets-Sheet 1 INVENI'OR 9 ,fffiw end/nyel INSPECTION ARRANGEMENTFOR AN AUTOMATIC SEWING APPARATUS Filed Nov; 10,1964

1966 1 SCHWENDINGER 5 Sheets-Sheet 2 lNVfNTOP u/ fcuead/Hf 1 N P.SCHWENDINGER 7 INSPECTION ARRANGEMENT FOR AN AUTOMATIC SEWING APPARATUSFiled NOV. 10, 1964 Q 5 Sheets-Sheet 3 O-CURRENT R'LAY'IIIIIIIIIIIIIIIIIIIII INVENTOR. Paa ,50/2 wen dz'zzgez BY Qua m UnitedStates Patent 3,276,577 INSPECTION ARRANGEMENT FOR AN AUTO- MATIC SEWINGAPPARATUS Paul Schwendinger, Wiesental, Germany, assiguor to Spinnereiund Webereien Zell-Schtinau Aktiengesellschaft, Zell, Germany, acorporation of Germany Filed Nov. 10, 1964, Ser. No. 410,232 Claimspriority, application Germany, Nov. 11, 1963, S 88,237 1 Claim. (Cl.209-74) This invention relates to automatic inspection of work pieces,and particularly to an automatic arrangement for inspecting work piecesproduced on a conveyorized automatic sewing apparatus, and for rejectingdefective pieces.

Defects in work pieces in the apparatus discussed are generally of twokinds. They may be optically ascertainable defects such as misweaves,spots, and visible defects, and they may be defects caused bymalfunctioning of the working implements of the apparatus such as amissing seam due to breakdown of a sewing head which are not readilydetected by optical devices. Malfunctioning of a working implement,however, is readily detected by means other than optical devices,particularly by sensing means arranged in the electrical drive circuitsof the working implements.

An object of the invention thus is the provision of an inspecting andsorting arrangement for automatic sewing apparatus and the like whichresponds to both aforedescribed types of defects in the work piecesprocessed.

Other objects and features of the invention will become apparent tothose skilled in the art as the disclosure is made in the followingdetailed description of a preferred embodiment of the invention asillustrated in the accompanying drawing in which:

FIG. 1 is a plan view of a memory device employed in the inspectionarrangement of the invention;

FIG. 2 shows the sorting station of an automatic sew-' ing apparatuswhich is controlled by the memory device of FIG. 1 in front elevation;and

FIG. 3 is a fragmentary side e-levational view, partly conventional, ofthe automatic sewing apparatus.

Referring now to the drawing, and initially to FIG. 1, there is seen adisk 1 on the periphery of which twelve signaling rods 2 are slidablymounted at uniform angular distances. The rods are arranged for radialmovement in respective hearings on the disk 1, and are retained in theirradial positions by frictional engagement with the bearings. Tensolenoids 3 are fixedly mounted about the circumferenece of the disk 1in respective positions A to K which are radially aligned with ten ofthe twelve rods 2 in the illustrated position of the apparatus. When asolenoid is energized, as shown in position F, an abutment 4 on thearmature of the solenoid engages the aligned rod 2 and pushes itradially inward from the normal position illustrated by all other rods.

The disk 1 is indexed about its axis by a mechanism which includes asolenoid 5, a crank rotatably supported on the non-illustrated shaft ofthe disk 1, connecting rod 6 attached to the armature of the solenoidand the crank, a pawl 7 mounted on the crank, and a ratchet 8cooperating with the pawl 7 and connected to the disk 1 for jointmovement by the common, non-illustrated shaft. When th solenoid 5 isbriefly energized, the disk 1 is indexed 30 about its axis into aposition in which again ten rods 2 are radially aligned with the tensolenoids 3 and their ab-utments 4.

A pulse or electrical signal received by one of the solenoids 3 is thusrecorded on the disk 1 by displacement of one of the rods 2 whichconstitute the memory elements of the illustrated device. The recordedsignal is read by a device consisting of an electric light bulb 9, a

3,276,577 Patented Oct. 4, 1966 'ice mirror 13, and a photoelectric cell10. After passing through positions A to K during the clockwise movementof the disk 1 indicated by an arrow, each rod 2 reaches a readingposition free from a solenoid 3. The reading device is arranged in sucha manner that the light beam from the light bulb 9 to the mirror 13 isintercepted by a rod at the reading position if it is in its normalposition. If the rod is inwardly displaced in the manner shown at F, thelight beam from the bulb 9 is reflected from the mirror 13 on thephotoelectric cell 10.

A stationary disk 11 coaxial with the stationary disk carries a cam 12arranged after the reading position of the rods to return an inwardlydisplaced rod 2 to its normal position during rotation of the disk 1.The output terminals of the photoelectric cell 10 are connected to amot-or switch 14.

FIG. 2 shows the sorting station of the automatic sewing apparatus whichis controlled by the memory device of FIG. 1. A finished work piece 15is supported on a conveyor belt 16 which is trained over several pulleysincluding a drive pulley 19. Rotation of the pulley 19 is energized byan electrically reversible motor 17 connected to the pulley 19 by a belt18. The motor is controlled by the afore-mentioned motor switch 14 insuch a manner that it moves the belt 16 in the direction of the arrow 21when the photoelectric cell 10 is shaded by a rod 2, and moves the belt16 in the direction of the arrow 22 when the photoelectric cell receivesa beam of light from the bulb 9. Depending on the direction of beltmovement, the work piece 15 is moved toward storage areas 20 and 20 foracceptable and rejected work respectively.

FIG. 3 shows a portion of the automatic conveyorized sewing apparatussufficient for an understanding of the invention. Work pieces arecarried on a conveyor belt 25 past a sewing head 26 at one of theconveyor stations. Belt movement is intermittently actuated by a driveshaft 27 on which a pulley 28 carrying the conveyor belt is mounted. Anidler pulley 29 which is driven by the moving conveyor belt carries acentrifugal switch 30. The switch is arranged in circuit with a currentsource 31 and the solenoid 5 to energize the solenoid during eachconveyor movement.

The sewing head 26 is equipped with an internal switch, not shown, whichinterrupts the current supply to the electric drive motor of the sewinghead when the sewing thread 32 breaks. A zero-current relay 33 in thesupply circuit of the sewing motor generates an electrical pulse uponinterruption of the current. This pulse is transmitted to the solenoid 3of the memory device associated with the work station at which thesewing head 26 is installed.

A spot light 34 illuminates the working area of the sewing station and awork piece located there. A conventional photoelectric sensing apparatus35, not shown in detail, is trained on the working area and generatesyet another signal in response to an optically ascertainable defect in awork piece at the station, the signal being transmitted to the asociatedsolenoid 3 for energizing the same.

While only one working and inspection station has been illustrated inFIG. 3, it will be appreciated that other stations will normally bearranged along the path of the work piece on the conveyor, each stationbeing equipped with signal generating means responsive either to asensed defect of the work piece or to malfunctioning of the workingimplement installed at the station, and connected to an associatedsolenoid 3 of the memory device illustrated in FIG. 1. The illustratedmemory device is intended for use with 12 stations of which 10 areequipped to generate signals.

After passing the several working and inspecting stations, the workpiece is transferred to the conveyor belt 16 of the sorting station nototherwise shown in FIG. 3, and described in more detail hereinabove withreference to FIG. 2.

Obviously, many modifications and variations of the present inventionare possible in the light of the above teachings. It is therefore to beunderstood that, within the scope of the appended claim, the inventionmay be practiced otherwise than as specifically described.

What is claimed is:

An automatic working and inspecting arrangement comprising, incombination:

(a) conveyor means for conveying a work piece in a predetermineddirection between a plurality of stations;

(b) working means arranged at one of said stations for working saidpiece;

(c) first signal generating means at said one station for sensing adefect in the conveyed piece and for generating a signal in response tothe sensed defect;

(d) second signal generating means connected to said Working means forgenerating a signal in response to malfunctioning of the same;

(e) sorting means at another one of said stations spaced from said onestation in said direction;

(f) a memory element;

(g) signal recording means connected with said first and second signalgenerating means and alignable with said memory element for recordingthe generated signals on said memory member when aligned therewith; (h)signal reading means alignable with said memory element for reading arecorded signal,

(1) said sorting means being operatively connected to said signalreading means for rejecting said Work piece at said other station inresponse to the read signal; and (i) actuating means for actuatingsimultaneous movement of said work piece from said one station to saidother station and of said memory element from a position of alignmentwith said signal recording means to a position of alignment with saidsignal reading means.

References Cited by the Examiner UNITED STATES PATENTS 2,132,447 10/1938Stout. 2,868,373 1/1959 Renard 209-74 2,962,655 11/1960 Wiley 209-74 X3,013,661 12/1961 Strubhar 209-74 X 5 M. HENSON WOOD, JR., PrimaryExaminer.

I. N. ERLICH, Assistant Examiner.

